To Instant Pot, add pasta, butter, mustard, garlic powder, salt, pepper and water.
Close the lid, turn pressure release valve to Sealing and press Pressure Cook on High or Manual for 3 minutes.
After allow pressure come down on its own for 8 minutes to prevent splatters all over your counter. Then turn pressure release valve to Venting to release remaining pressure.
Open the lid and gently stir the pasta. Add cheese in portions, stirring in between. It might look stringy. Then add milk in 1/4 cup portions until desired consistency, stirring in between. Mac and cheese will become creamy.
Serve hot and immediately for best results.
Video
Notes
Store: Refrigerate leftovers in an airtight container for up to 2 days. Or make less, by cutting recipe ingredients in half and keep same cook time. Reheat on Sauté in Instant Pot and add a splash of water or milk, then stir gently until heated through.
Freeze:Pasta doesn’t freeze well.
For gluten free pasta: I would cook it for 1 minute with same 8 minute pressure release.
If pasta appears undercooked: Usually due to altitude or whatever other reason because it is Instant Pot. Then close the lid, let it sit for 5 minutes and it will get there.
Instant Pot size: No changes to recipe necessary if using 3 quart Instant Pot. Recipe can be doubled in 6 or 8 quart Instant Pot only.